Piston Service Life

Does anyone know the specification for Piston Service Life? I have done a lot of research but was unable to locate any information. I am guesing its somewhere ariubs 20 hours.

Uh, no. You can't find it because there isn't one. If it was 20 hours I'd be replacing the piston ever two weeks. The last bike had nearly 17,000 miles on it before it was stolen and I never even had to check the valves (first check is at 26,000 miles), no motor maintenance beyond oil changes and cleaning the air filter.

This bike isn't like the WRF's.

I know of R1's (same piston) with well over 100,000 miles on the same top end.

Going by dbparti's user image and looking at his past posts, I think he's got an Athena big bore kit in his bike.
I don't know for sure how long these are known to go before blowing sky high, but I'd hope it's a lot more than 20 hours worth of typical use.

What I'd do is do a search for threads with the words "Athena big bore" or something like that and contact those guys posting with your questions.
Maybe they'll tell you what their milage is currently at to give you an idea. :)

just had my piston and cam chain replaced, almost 37,000 the cam chain was well stretched, about a link. the piston had some wear but not to bad. everything else looks good. rode the the bike and everything is tight and a lot quieter.

the motor had some knocking and piston slap noise so i knew it was time.

drater wrote:

just had my piston and cam chain replaced, almost 37,000 the cam chain was well stretched, about a link. the piston had some wear but not to bad. everything else looks good. rode the the bike and everything is tight and a lot quieter.

the motor had some knocking and piston slap noise so i knew it was time.

Did you get it replated too? or just a new piston.

I figured the top end would last to about 50k.

I recall Yamaha stating somewhere that they have engineered the engine to do 100,000kms before it needs a rebuild - can not remember where I read that though ...

every thing looked good and that plating in the cylinder is really strong. put a new cam chain, that was probably more needed then anything, it was knocking pretty good.

changed the oil and filter after riding and it looked good, not much metal flakes, rode it hard. it's all good.